Testifying before the House Energy and Commerce Committee, McCarthy told Pompeo that the agency was unable to determine whether or not its policies have affected the 26 indicators of global warming that the agency lists on its website.

“It’s unlikely that any specific one step is going to be seen as having a visible impact on any those [indicators] — a visible change in any of those [indicators],” McCarthy said.

Pompeo asked McCarthy how many heat-related deaths—one of the indicators the EPA lists—had been eliminated by the agency’s 2010 regulations on vehicular greenhouse-gas emissions. McCarthy said that neither she nor the congressman could make “direct connections.”

That didn’t stop McCarthy from announcing new regulations on carbon limits for the nation’s power companies in a speech Friday at the National Press Club. New gas-fired plants will be limited to 1,000 pounds of carbon dioxide per megawatt hour; new coal-fired plants will be allowed 1,100 pounds. According to the New York Times, the average advanced coal plant currently puts out roughly 1,800 pounds of CO2.

“The overwhelming judgment of science tells us that climate change is real, human activities are fueling that change, and we must take action to avoid the most devastating consequences,” McCarthy said.